Which species is in serious decline, particularly in western North America?
b) Mangrove cuckoo
c) Black-billed cuckoo
d) Greater roadrunner
Answer: a) Yellow-billed cuckoo. In 2014, the U.S. Fish and Wildlife Service listed the western population of the yellow-billed cuckoo as a threatened species under the Endangered Species Act. This cuckoo is still relatively common in the East, but biologists estimate that more than 90 percent of the bird’s breeding habitat in the West has disappeared in the last 50 years.